For a bag filter, whether the design is reasonable and the operation is normal is mainly reflected in the service life of the filter bag and the operating resistance of the equipment. In some cases, the damage of the filter bag is related to the high operating resistance of the equipment. Reasonable structural design, parameter determination, and accessory selection are important links for the successful operation of bag filters. Reasonable, correct, and proper management and maintenance during equipment operation are essential for the successful operation of bag filters.
1. Qualitative analysis of high resistance
Bag filter is a dust removal and purification equipment that uses filter media to filter dusty gases. It has the characteristics of dust removal, simple structure, strong adaptability, and stable operation. It is widely used in industries such as metallurgy, thermal power generation, and cement manufacturing. However, during the production process, it is common to encounter high equipment operating resistance, leading to a decrease in dust removal efficiency and a shortened lifespan of filter bags. When the operating resistance of a bag filter exceeds 1500Pa, we can qualitatively say that the operating resistance of this dust collector is too high. When the operating resistance of the dust collector exceeds 2000Pa, it will have a significant impact on the ventilation of the entire system.
2. Reasons for high resistance
The operating resistance of the dust collector is caused by three parts: the body, the filter bag, and the dust adsorbed on the filter bag. Factors such as structural design differences, filter material, filtration wind speed, gas dust concentration, dust particle size, and gas humidity have a significant impact on the operating resistance of dust collectors.
3. The influence of structural design on the operating resistance of dust collectors
The structural design includes the cross-section of the inlet and outlet air ducts, the uniform air device of the large bag filter, the cross-sectional dimensions of various parts through which the airflow passes, as well as the design of air locking, maintenance door sealing, equipment insulation, etc. Unreasonable structural design can result in high operational resistance of the equipment, while a reasonable structural design can result in a body resistance of around 400Pa. It is recommended that the wind speed of the inlet and outlet ducts should be less than 15m/s, with a wind speed of around 10m/s being optimal. The wind speed of the inlet and outlet branches of each bag room should be less than 10m/s, which is beneficial for both uniform air flow and reducing resistance.
Performance characteristics of bag filter:
1. Adopting low-pressure pulse blowing technology for dust cleaning and low energy consumption.
Use a straight through low-pressure pulse valve. The injection pressure is only 0.2-0.4MPa, with low resistance, fast opening and closing, and dust cleaning. Due to the good cleaning effect and long cleaning cycle, the energy consumption of blowback gas is reduced.
2. The air duct adopts a collection pipe layout with a compact structure.
3. The entire operation process of the dust removal equipment using a PLC programmable controller.
Using differential pressure or timing control methods, it has high performance, long service life, and is easy for users to operate and use.
Specifications and technical parameters: 1. RFLML low-pressure pulse jet long bag dust collector, divided into RFLML390 and RFLML970
4. Electromagnetic pulse valves have a long service life and good performance.
Due to the low injection pressure (0.2-0.4MPa), the pressure and impact force on the pulse valve diaphragm during opening and closing are relatively low. At the same time, due to the longer cleaning cycle, the number of times the pulse valve is opened is correspondingly reduced, thereby extending the service life of the pulse valve and improving its usability.
5. The equipment has low operating resistance and good spraying effect.
The dust collector adopts a segmented pulse back blowing offline dust cleaning method, which avoids the phenomenon of dust being repeatedly adsorbed, improves the effectiveness of pulse blowing dust cleaning, and reduces bag resistance.
6. The filter bag is easy to install and remove, and can be fixed
The bag filter adopts an upper suction method. When changing the bag, the filter bag skeleton is extracted from the clean air chamber of the dust collector, and the dirty bag is put into the ash hopper, which is then taken out through the ash hopper hole to create a bag changing environment. The filter bag is fixed to the flower plate hole by the elastic expansion ring at the bag mouth, which is firmly fixed and has good sealing performance.
